1、Designation: D3848 03 (Reapproved 2013)Standard Test Methods forRubberEvaluation of NBR (Acrylonitrile-ButadieneCopolymers) Mixed With Carbon Black1This standard is issued under the fixed designation D3848; the number immediately following the designation indicates the year oforiginal adoption or, i
2、n the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods specify the standard materials, testformula, mixing procedures,
3、 and test methods for the evalua-tion of acrylonitrile-butadiene rubber (NBR) mixed with car-bon black.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,
4、 if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D412 Test Methods for Vulcanized Rubber and
5、Thermoplas-tic ElastomersTensionD1646 Test Methods for RubberViscosity, StressRelaxation, and Pre-Vulcanization Characteristics(Mooney Viscometer)D2084 Test Method for Rubber PropertyVulcanizationUsing Oscillating Disk Cure MeterD3182 Practice for RubberMaterials, Equipment, and Pro-cedures for Mixi
6、ng Standard Compounds and PreparingStandard Vulcanized SheetsD3896 Practice for Rubber From Synthetic SourcesSamplingD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD5289 Test Method for Rubber PropertyVulcanizationUsing Rotorles
7、s Cure MetersD6204 Test Method for RubberMeasurement of Unvulca-nized Rheological Properties Using Rotorless Shear Rhe-ometers3. Significance and Use3.1 These test methods are mainly intended for refereepurposes but may be used for quality control of rubberproduction. They may also be used in resear
8、ch and develop-ment work and for comparison of different samples in astandard test formula.3.2 These test methods may also be used to obtain values forcustomer acceptance of rubber.4. Standard Test Formula4.1 Standard Formula:IRM/SRMSRM Quantity, PartsMaterial No. By MassMasterbatch . 100.00 + XAZin
9、c oxideB3.00Sulfur, coatedC. 1.50Stearic acidB1.00TBBSDB0.70 + XTotal mass 106.20 + XBatch factorsMillEMiniature internal mixerFAX = parts carbon black per 100 parts base polymer.BUse current IRM/SRM.CThe use of 2 % MgCO3coated sulfur is recommended. Standard 2 % MgCO3coated sulfur Lot No. M266573-P
10、 is available from C. P. Hall Co., 4460 HudsonDrive, Stow, OH 44224.DN-tert-butyl-2-benzothiazolesulfenamide.EFor mill mixing, a batch factor should be selected to the nearest 0.5 to give aslarge as total mass as possible that will not exceed 525.0 g. Calculate all parts tothe nearest 0.01 part. Wei
11、gh the masterbatch to the nearest 1 g, the sulfur and theaccelerator to the nearest 0.02 g, and all the other compounding materials to thenearest 0.1 g.1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.23 on SyntheticR
12、ubbers.Current edition approved Nov. 1, 2013. Published January 2014. Originallyapproved in 1980. Last previous edition approved in 2009 as D3848 03 (2009).DOI: 10.1520/D3848-03R13.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.or
13、g. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1FFor MIM mix, select a batch factor to give a batch that will fill
14、 the mixing chambervolume to 75 % capacity. Calculate all parts to the nearest 0.1 g, the compoundingmaterial blend to the nearest 0.01 g, and the individual compounding materials, ifused, to the nearest 0.001 g.For the MIM procedure, it is recommended that a blend of compoundingmaterials be prepare
15、d to improve accuracy in the weighing of the materials. Thecompound material blend is prepared by blending a proportional mass of eachmaterial in a biconical or a vee blender. A mortar and pestle may be used forblending small quantities.5. Sample Preparation5.1 Obtain and prepare the test samples in
16、 accordance withPractice D3896.6. Mixing Procedures6.1 Three mixing procedures are provided as follows:6.1.1 Method AMill Mix (6.2) and6.1.2 Method BMiniature Internal Mixer Mix (6.3).6.1.3 Method CInternal MixerNOTE 1It is not implied that comparable results will be obtained bythese test methods.6.
17、2 Method AMill Mix Procedure:6.2.1 For general mixing procedures, refer to PracticeD3182.6.2.2 Mixing CycleInitial Mix:Accu-Dura- mula-tion, tive,min min6.2.2.1With the mill roll temperature set at 50 5C(122 9F) and the mill opening set at 1.40mm (0.055 in.), band the masterbatch on theslow roll wit
18、hout cutting.226.2.2.2Add sulfur slowly and evenly across the millat a uniform rate.246.2.2.3Add stearic acid. Make one34 cut from eachside after the stearic acid has beenincorporated.266.2.2.4Add the zinc oxide and the accelerator. 3 96.2.2.5Make three34 cuts from each side and cutthe batch from th
19、e mill.2116.2.2.6Set the rolls at 0.8 mm (0.032 in.). Pass therolled batch endwise through the mill six times.2136.2.2.7Open the mill to give a minimum batchthickness of 6 mm (0.25 in.) and pass the stockthrough the mill four times, folding it back onitself each time.1146.2.2.8Check the batch mass a
20、nd record. If it differsfrom the theoretical value by more than 0.5 %,discard the batch.6.2.2.9From this batch cut a sample for testing ofcompound viscosity in accordance with TestMethods D1646 or rheological properties in ac-cordance with Test Method D6204, vulcanizingcharacteristics in accordance
21、with Test MethodD2084, or Test Method D5289, or both, if theseare desired. Condition the sample for 1 to 24 hat 23 2C (73.4 3.6F) before testing.6.2.2.10If tensile stress is required, sheet off thecompound from the mill at a setting to give afinished gage of approximately 2.2 mm (0.085in.) by passin
22、g the folded stock between therolls set at 50 5C (122 9F) four timesalways in the same direction to obtain theeffect of milling. Cool on a flat, dry metalsurface.6.2.2.11For routine laboratory testing, condition thesheeted compound for 1 to 24 h at 23 2C(73.4 3.6F) and a relative humidity notgreater
23、 than 55 %. For maximum precision,condition for 1 to 24 h in a closed container toprevent absorption of moisture from the air orin an area controlled at 35 5 % relativehumidity.6.3 Method BMiniature Internal Mixer (MIM) Procedure:6.3.1For general mixing procedures, refer toPractice D3182. Mix with t
24、he MIM mixingchamber maintained at 60 3C (140 5F)and with an unloaded rotor speed of 6.3 to 6.6rad/s (60 to 63 rpm).6.3.2Prepare the masterbatch by passing itthrough a mill one time with the temperatureset at 50 5C (122 9F) and an opening of0.5 mm (0.02 in.). Cut the sheet into strips thatare approx
25、imately 25 mm (1 in.) wide, ifdesired.6.3.3 Mixing Cycle:6.3.3.1Feed the rubber strips into the mixingchamber and, when all are in, start the timer.Break down the rubber.0.5 0.56.3.3.2Add all the zinc oxide, sulfur, stearic acid,and TBBS which have previously been blendedtogether, taking care to avo
26、id any loss. Stopthe mixer briefly and sweep loose pigments intothe chamber with a brush.0.5 1.06.3.3.3Allow the compound to mix.6.3.3.4Turn off the motor, raise the ram, remove themixing chamber, and discharge the batch.Record the maximum batch temperature, ifdesired.8.0 9.06.3.3.5Pass the batch be
27、tween the rolls of a millmaintained at 50 5C (122 9F) and 0.5mm (0.020 in.) opening once, then twice at 3.0mm (0.122 in.) opening.6.3.3.6Check the batch mass and record. If it differsfrom the theoretical value by more than 0.5 %,discard the batch.D3848 03 (2013)26.3.3.7Cut a sample for testing of co
28、mpoundviscosity in accordance with Test MethodsD1646 or rheological properties in accordancewith Test Method D6204, or vulcanizing charac-teristics in accordance with Test MethodD2084, or Test Method D5289, if these are de-sired. Condition the sample 1 to 24 h at 23 2C (73.4 3.6F) before testing.6.3
29、.3.8If stress strain testing is required, pass therolled stock end-wise through the mill six timeswith the mill temperature at 50 5C (1229F) and a roll separation of 0.8 mm (0.032in.).6.3.3.9If tensile stress is required, sheet off thecompound from the mill at a setting to give afinished gage of app
30、roximately 2.2 mm (0.085in.) by passing the folded stock between themill rolls set at 50 5C (122 9F) four timesalways in the same direction to obtain theeffect of milling. Cool on a flat, dry metalsurface.6.3.3.10For routine laboratory testing, condition thesheeted compound for 1 to 24 h at 23 2C(73
31、.4 3.6F) and a relative humidity notgreater than 55 %. For maximum precision,condition for 1 to 24 h in a closed container toprevent absorption of moisture from the air orin an area controlled at 35 5 % relativehumidity.6.4 Internal Mixer Procedure:6.4.1 For general mixing procedure refer to Practic
32、e D3182.6.4.2 Mixing Cycle-Initial Mix:Accu-Dura- mula-tion, tive,min min6.4.2.1Adjust the internal mixer temperature toachieve the discharge conditions outlined in6.2.2. Close the discharge gate, start the rotorat 8.1 rad/s (77 rpm) and raise the ram.006.4.2.2Charge one half the rubber, all of the
33、zincoxide, carbon black, stearic acid, and then theother one half of the rubber. Lower the ram.53.0.53.56.4.2.3Allow the batch to mix. .5 4.06.4.2.4Raise the ram and clean the mixer throat andthe top of the ram. Lower the ram.2.0 6.06.4.2.5Allow the batch to mix until a temperature of170C (338F) or
34、a total mixing time of 6 min isreached, whichever occurs first. Discharge thebatch.2.0 6.06.4.2.6Determine and record the batch mass; if themass differs by more than 0.5 % of thetheoretical mass, discard the batch.6.4.2.7Pass the batch immediately through thestandard laboratory mill three times, set
35、 at 6.0mm (0.25 in.) and 40 5C (104 9F).6.4.2.8Allow the batch to rest for 1 to 24 h.6.4.3 Final Mix:6.4.3.1 Adjust the internal mixer temperature to 40 6 5C(104 6 9F), turn off steam and turn on full cooling water tothe rotors, at 8.1 rad/s (77 rpm), and raise the ram.Accu-Dura- mula-tion, tive,min
36、 min6.4.3.2Charge12 the batch, with all the sulfur andaccelerator rolled into this portion of the batchbefore feeding to the mixer. Add the remainingportion of the batch. Lower the ram.556.4.3.3Allow the batch to mix until a temperature of110 5C (230 9F) or a total mixing time of3 min is reached, wh
37、ichever occurs first.Discharge the batch.2.5 3.06.4.3.4Determine the record the batch mass; if themass differs by more than 0.5 % of thetheoretical mass, discard it.6.4.3.5With the rolls of a standard laboratory millmaintained at 40 5C (104 9F) and set at0.8 mm (0.0032 in.) opening, pass the rolledb
38、atch endwise through the rolls six times.2.0 5.06.4.3.6Open the rolls to give a minimum thicknessof 6 mm (0.25 in.) and pass the compoundthrough four times, folding it back itself eachtime.1.0 6.06.4.3.7Cut enough samples for testing of compoundviscosity in accordance with Test MethodsD1646, or rheo
39、logical properties in accordancewith Test Method D6204, or vulcanizing charac-teristics in accordance with Test MethodD2084, or Test Method D5289, if these are de-sired. Condition the sample for 1 to 24 h at 23 3C (73.4 5.4F) before testing.6.4.3.8If tensile stress is required, sheet off thecompound
40、 from the mill at a setting to give afinished of approximately 2.2 mm (0.085 in.) bypassing the folded stock between the rolls setat 50 5C (122 9F) four times always in thesame direction to obtain the effects of milldirection. Cool on a flat, dry metal surface.6.4.3.9Four routine laboratory testing,
41、 condition thesheeted compound for 1 to 24 h at 23 3C(73.4 5.4F) and a relative humidity notgreater than 55 %. For maximum precision,condition for 1 to 24 h in a closed container toprevent absorption of moisture from the air orin an area controlled at 35 5 % relativehumidity.D3848 03 (2013)37. Test
42、for Cure Characteristics Using the Cure Meter7.1 Measure vulcanization characteristics with an Oscillat-ing Disk cure meter in accordance with Test Method D2084 ora Rotorless Cure Meter in accordance with Test MethodD5289.7.2 The recommended standard Oscillating Disk test condi-tions are: 1.7 Hz osc
43、illation frequency; 61 amplitude ofoscillation, 160C die temperature, 30-min test time, and nopreheating. The recommended test conditions for the RotorlessCure Meter are: 1.7 Hz oscillation frequency, 60.5 of arc fortorsional shear cure meters and 60.05mm for linear shear curemeters, 160 C die tempe
44、rature, 30 min test time, and nopreheating. Tolerances for the listed conditions are included inthe specified test methods.7.3 The recommended standard test parameters are: ML,MH, tsl, t50 and t90.8. Preparation and Testing of Vulcanizates8.1 An alternative to measuring vulcanization parameters isth
45、e measurement of stress-strain properties of vulcanizates inaccordance with Test Methods D412. Prepare test sheets andvulcanize them in accordance with Practice D3182.8.1.1 The recommended standard vulcanization times forthe mill mixed compound are 20, 40, and 60 min at 150C(302F). The recommended s
46、tandard vulcanization time for theminiature internal mixer compounds is 40 min at 150C.NOTE 2Vulcanization times of 25, 50, and 75 min at 145C (293F)for the mill-mixed compounds and 50 min at 145C for the MIM-mixedcompounds may also be used, but will not necessarily give the sameresults as the recom
47、mended standard vulcanization conditions.8.1.2 Condition all vulcanizates for 16 to 96 h at a tempera-ture of 23 6 2C (73.4 6 3.6F) prior to making stress-straintests.NOTE 3Quality control of rubber production may require testingwithin 1 to6htoprovide close surveillance of plant operations; however,
48、slightly different results may be obtained.8.1.3 Prepare test specimens and obtain tensile stress, ten-sile strength, and elongation in accordance with Test MethodsD412.9. Precision and Bias39.1 This precision and bias section has been prepared inaccordance with Practice D4483. Please refer to this
49、practicefor terminology and other statistical calculation details.9.2 The precision results in this precision and bias sectiongive an estimate of the precision of this test method with thematerials (rubbers, etc.) used in the particular interlaboratoryprogram as described below. The precision parameters shouldnot be used for acceptance or rejection testing of any group ofmaterials without documentation that the parameters are appli-cable to t
